Inconsistent Improperly Rendering Water?

So through feedback of my map I keep getting the occassional "Water isn't loading" and reading the chat I see from random people "Water is Purple and Black" (Which would mean invalid textures). However, it renders properly for others, including myself (I've seen others post screenshots in feedback with the water showing up properly as well). What is the issue?

The water texture in question is water/water_well, and I do have env_cubemaps

I keep hearing that but I do have the env_cubemaps added (and as far as I know you don't need anything else in particular but an env_cubemaps added) though, so unless I'm missing something that shouldn't be an issue.

Yeah, TF2 is different from all other Source games (using the older engine, if you have a game running on Source 2012 and up you also need to do additional steps) when building cubemaps. It's not as simple as typing buildcubemaps in the console and boom, done.